1. Field of the Invention
The present invention relates to a tool for working or laboring soil, preferably for agricultural labors such as tilling, cultivating, cutting and chopping haulm and stubble, planting, closing furrows, opening furrows, fertilizing and any other similar work, and more particularly the invention refers to a tool such as a plowing implement, disc, chopping disc, colter, for agricultural machines like plows, planters and the like. More particularly, the invention is related to the configuration and mounting of the disc tools for assisting and improving the replacement, restoration and repairing of the same when is necessary.
While a particular reference will be made in this specification to a colter or plowing disc, it is to be remarked that the concepts of the invention may be applied to any other working tool that needs to be rotatably mounted onto a shaft, preferably for freely rotation on the shaft.
2. Description of the Prior Art
It is well known to provide working disc tools, such as colters or plow discs that are stationary or rotatably mounted on corresponding shafts, which shafts are in turn mounted in a frame or machine. These kind of discs comprise a disc member and a cast iron hub that is affixed to the disc member by means of riveting, bolting or welding, for example. The hub forms a cavity for receiving a ball bearing previously tightly fixed onto a shaft. Then a nut is threadably connected to the shaft to retain the assembly in the hub.
In order that the hub is able to be affixed to the disc, the hub must be previously processed by a series of machining steps with the purpose of appropriately centering the hub in the disc, this centering of the hub, and hence of the bearing, being essential to prevent the disc from excentrically rotating what would result in a premature blunt of the disc cutting edge and even in the braking of the disc.
Due to the high number of components in these tools and the number of machining steps necessary to place them in proper conditions to work, the final cost of each disc assembly is very high. Considering that a planting or plowing machine comprises a plurality of such discs this cost is an important part of the machine cost, as well as in the costs of maintenance and service required by the disc tools. The time required for the servicing of these discs is excessive in such an extent that when a disc is damaged the user opts for directly replacing the same by a fresh one. It is common that a disc results damaged and unable to service during the working in the country, perhaps far from a servicing store, thus a number of tools must be carried in the planting or plowing machine for repairing or removing the disable disc.
In the event the machine operator has no proper tools to repair the damaged disc or discs the entire machine may become disable and the soil working must be interrupted to move the machine to a repairing site in the country or farm. If the disc is of the type having the hub riveted to the disc, the only way to replace the disc or the bearing is by cutting the rivets with a hammer and chisel. This action, however, may be dangerous to the integrity of the disc which may result broken or damaged by the hammering. Even when the hub and the bearing are satisfactorily removed from the disc member, the disc should be replaced by a fresh one because the orifices for the rivets in former disc generally result deformed and oversized because of the chiseling and hammering actions to remove the old rivets.
It would be therefore desirable to have a tool such as a plow disc, a colter and the like, made simple, with few and simple components, with removable fasteners for mounting the disc in the machine, and requiring simple and cheaper servicing.
It is therefore one object of the present invention to provide a tool for working the soil in agricultural labors such as tilling, cultivating, cutting, chopping haulm and soil, fertilizing works, closing and opening furrows, and the like, the tool comprising a metallic disc member having a center portion thereof shaped into a housing integrally forming one piece with the disc member, the housing having an inner wall forming fit mounting means for tightly receiving a bearing, such as a ball or needle bearing. Preferably the housing comprises a tubular portion formed in the disc member by stamping or by forging.
It is another object of the invention to provide a tool for working the soil in agricultural labors such as tilling, cultivating, cutting, chopping the haulm and soil, closing furrows, and the like, the tool comprising a metal disc member having a housing defined by a tubular portion projecting from the disc member and having mounting means comprising a first opening at one side of the disc member and a second opening at an opposite side of the disc member, the first opening having a first diameter for receiving a bearing and the second opening having a second diameter smaller than the first diameter to prevent the bearing to pass through the second opening. The tubular portion and the disc member comprises only one piece and the tubular portion is preferably formed by stamping or forging.
It is a further object of the present invention to provide a tool for working the soil in agricultural labors such as tilling, cultivating, cutting, chopping the haulm and soil, closing furrows, the tool comprising a metal disc member having a center portion thereof shaped into a housing integrally forming one piece with the disc member, the housing having an inner wall forming fit mounting means for tightly receiving a bearing, a bearing tightly received into the housing, a washer affixed to the disc member and retaining the bearing into the housing, a shaft having an end with a seat portion and a threaded portion, the bearing being tightly fit in the seat portion of the shaft, a nut threadably fixed onto the threaded portion thus retaining the bearing and the shaft together, and a dust cap provided over the nut to prevent dust from enter the threads of the nut and shaft.
The above and other objects, features and advantages of this invention will be better understood when taken in connection with the accompanying drawings and description.